By BBC News Online's Katherine Sellgren at the NAHT conference in Harrogate

School governor posts are becoming increasingly difficult to fill because of the onerous duties involved, head teachers have warned.

Governors should be involved in shaping the future of the school, rather than deciding how much can be afforded for text books and new windows, heads say.

The expectation that part-time, unpaid volunteers could fulfil effectively and efficiently the responsibilities
thrust upon them was unrealistic, delegates at the annual conference of the National Association of Head Teachers said.

Heads are calling on the government to give them greater freedom to conduct school business, leaving governors to take on an advisory role.

When the head teacher of a British school in Ankara, David Draper, asked conference delegates how many of them found it hard to fill all their governing body vacancies, over 50% put their hands up.

Governors often did not last long in their post, making turn-over a real problem.

Training time

And time spent training new governors could be put to better use, Mr Draper said.

"We know we're good enough to run schools effectively," he said.

The head teacher of Whitehill Junior School in Gravesend, Kent, Peter Hamilton, said the number of governor vacancies reflected the heavy responsibility put upon them.

Mr Hamilton - who had no applications for four parent-governor positions last year - said it was too much to expect of people with no background in education.

"Far too much is expected of them, which is one of the biggest reasons they're not coming forward.

"And they're also worried about what their liability is if things go wrong.

"For example, if there's a personnel issue and someone is claiming unfair dismissal, are they going to find themselves in a tribunal? There is a certain fear factor," Mr Hamilton said.

Think-tank

He believes that the role of governors should be developed into a kind of think-tank, where they decide the school's policy, leaving the head to implement it.

"Rather than at the moment, where we - the senior management - decide the policy in school meetings and then have to get it approved by the governors," he said.

The current system led to a situation where he spent endless hours in meetings discussing the same issues over and over again.

"The time could be more productively spent with children," Mr Hamilton said.

No payment

But he does not believe there is an argument to pay governors to address the shortage of volunteers.

"It would create a different climate, with different people coming forward, like retired heads looking to supplement their pensions.

"They'd become more accountable and who would pay them anyway? It couldn't come from the school's budget," Mr Hamilton said.